Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Hardiness Zones
USDA Hardiness Zones 3 to 7, excellent cold tolerance, moderate heat tolerance, goes dormant and turns brown in extreme summer heat unless irrigated.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
Standard turf-type blend (e.g., 'Midnight' or 'Baronie')
About This Grass
Forms a dense, high-quality turf with medium-fine texture and a rich, dark to medium green color. Grows 1.5 to 2 feet tall if unmowed, but maintained at 1.5 to 2.5 inches in lawns. Produces pyramid-shaped panicle seed heads at maturity.
Blade Characteristics
Medium-fine width (2-3mm), flat to folded shape with distinctive boat-shaped tips and prominent parallel parallel veins giving a railroad-track appearance. Folded in the bud (vernation). Ligule is short and membranous, auricles absent.
Root System
Moderately deep fibrous root system combined with vigorous underground rhizomes. Moderate thatch-forming tendency under high fertility. Slow to germinate and establish from seed, but creates a tough, wear-recovering dense sod once mature.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized throughout North America and temperate regions worldwide
Growth Habit
Aggressively rhizomatous, spreading underground to form a dense, uniform sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high watering needs, goes into summer dormancy during severe drought but recovers well when moisture returns. Prefers well-drained, fertile soils with pH 6.0-7.0.
Mowing & Maintenance
Mow at 1.5 to 2.5 inches frequency 1-2 times weekly during peak growth. High fertilizer requirement (3-5 lbs N per 1000 sq ft per year). Requires regular dethatching and aeration due to dense rhizome and turf mat.
Special Characteristics
Exceptional wear tolerance and self-repairing capability via rhizomes. Good cold hardiness and winter color retention in milder winter zones. Susceptible to certain diseases like dollar spot, summer patch, and leaf spot.
Ecological Information
Introduced species in North America. Provides good soil stabilization and erosion control through its dense root and rhizome network. Commonly blended with Perennial Ryegrass and Tall Fescue in northern turf mixes.